U-shaped micro-groove fiber based on femtosecond laser processing for humidity sensing

• 来源期刊: 光电子快报（英文版）
• 年，卷（期）: 2018,（3）
• 页码范围: 212-215
• 页数: 4页
• 语种: 英文
• DOI: 10.1007/s11801-018-7262-3

摘要

A novel optical fiber sensor with a U-shaped micro-groove structure ablated by femtosecond laser on single-mode fiber for measuring air relative humidity (RH) is reported in this paper.In order to improve the accuracy of sensor,a graphene oxide (GO)/polyvinyl alcohol (PVA) composite film is coated on the surface of micro-groove structure.In the U-shaped micro-groove structure,the remaining core and micro-cavity in the micro-groove make up two major optical propagation paths,forming a Mach-Zehnder interferometer (MZI).The sensor has a good linear response within the RH range of 30％-85％,and the maximum sensitivity can reach 0.638 1 nm/％RH.The effect of temperature on the overall performance of the humidity sensor is also investigated.As a new type of all-fiber device,the sensor shows excellent sensitivity and stability.